You can make purchase from taobao. But it's suggested to make it with an agent's help to avoid potential troubles and obstacles, even though you need to pay some commission to them. But as a efficient business, it's still worth as long as you can find good source on taobao.
I'm introducing http://www.FreeShoppingChina.com, which is a purchase agent company as well as taobao agent who helps buyers to purchase from taobao and 1688.com(wholesale) since 4 years ago. I'm working in this company, frankly speaking, and I know a lot in this area.
Agents can help a lot on payment, communication, product inspection, return/change/refund, parcel consolidation, cheap shipping and etc...And these will always be the problems/obstacles in your direct orders to taobao sellers without an agent. Agent's value is to solve these problems. BTW, the rate of return/change/refund is about 2%-10%, depending on different sellers, product categories, selling seasons.
Most agents charges 8%-15% as commission. I don't suggest you select the cheapest as you also need to look into their service scope, response time, shipping discount, customer service and so on. Some of them may become your extra purchase cost in the view of a business, even though the commission is lower..
Try find a reliable company based agent is suggested. And our company is one of them.